In order to elucidate a link between the sediment oxygen consumption (SOC) and the benthic environment, field observations of water quality and sediment environment were carried out during summer to autumn at 4 sites in the head of Tokyo Bay in 2009. SOC was observed by chamber methods after sampling by using fluorescent DO meter at a laboratory. The benthic environment was observed by a CN ratio and the quinine profile methods. Water quality on the seabed was also measured including DO, sulfide and nutrients at the same time. SOC was positively correlated with quinine concentrations. This correlation was the same level as water temperature, salinity and sulfide. From the long-term oxygen consumption experiments, influence of sediment microbial community was also confirmed.
